Every now and then, when reading a wildly preposterous news report, a consoling voice pipes up from the subconscious. “Don’t fret, it isn’t happening,” it whispers. “Remember how you dreamed the other day that England won the 2014 World Cup in Brazil and that Bob Diamond sought penance, Profumo-style, by devoting the rest of his days to doing good works in the East End? And what about the one where George Osborne was Chancel… all right, that one’s the exception that proves the rule.” “But look,” soothes the subconscious, “you have a fever. This is one of those flu-y nightmares, so hush now and get some rest.” Then you wake up, take a couple of paracetamol, and forget all about it.

Being in the latter stages of bronchitis, I am waiting to come round from just such a dream. Yet every line that appears on the computer screen makes it harder to ignore the fact that dreams seldom involve the dreamer typing them up. So unless I have awoken by the start of the next paragraph, there will be no choice but to accept as plain fact that on Thursday, at a barely quantifiable cost in money and man-hours, a stretch of motorway was closed by anti-terrorist police because someone smoked an electronic cigarette on a coach.

Nope, I’m still at the desk. It must have happened after all, in which case perhaps this is the moment to reprise the facts, partly for anyone who missed it, and partly in a futile attempt to make sense of the incident itself. Shortly before 8.30am on Thursday, on the M6 Toll in Staffordshire, someone on a Megabus coach from Preston to London noticed smoke coming from a fellow passenger’s mouth or bag, depending on which report is accurate. Being a sporadic e-fag smoker, particularly during bouts of bronchitis, I am aware that part of what makes it such a brilliant simulation is the emission of smoke. The traveller in question, who presumably wasn’t aware of this, called 999, and understandably so in the post-shoe-bomber age.

It is what ensued that has the flavour of the surreal nightmare, or possibly a scene from one of those mesmerisingly dreadful British comedy films in which the likes of Jimmy Carr invest, because the tax relief, once the film has grossed a total of £17.40 on general release, is worth 10 times the initial investment.

No one would deny that the police had a duty to investigate. Whether that duty extended beyond sending a few cars to guide the coach to the hard shoulder and question the suspect, to satisfy themselves that there is such a thing as smoke without fire, is another matter. In fact, it extended to ringing the coach with hundreds of police, military personnel, ambulances and an estimated 16 fire crews.

Related Articles

Why the 48 passengers, traumatised and tearful, were held on the coach for three hours if the anti-terrorist geniuses genuinely feared an imminent explosion is anyone’s guess. They were then frogmarched off, at gunpoint, and into a “decontamination zone”, where they were made to sit cross-legged in silence for another hour before being frisked and released.

All right, it is easy to be glib, and there are bad people out there with bad intentions, and with the Olympics imminent, better a very mild overreaction than the laxity that enables something horrendous. Yet there is a middle way between blithely allowing wicked people to detonate bombs at the one extreme, and at the other, terrorising the innocent while causing a seven-hour jam over something a police commander on speaking terms with competence could have resolved in 10 minutes.

So bizarre does this seem, in fact, that one naturally seeks a more flattering interpretation. Even the British police are not so cataclysmically dim when it comes to basic risk assessment, you want to believe, that it could have been a cock-up. Admittedly, this construction requires wilful amnesia about poor Jean Charles de Menezes (the whole incident has a vividly retro feel, as if the police thought it was July 2005), but we always seek the charitable explanation… in this case that it was conceived as a devilishly subtle coded warning to those plotting Olympic mayhem that the game isn’t worth the candle (and God help Wee Willie Winkie if he wanders through town carrying one of those).

If so, what a master-stroke. Any terrorist cell eager to paralyse London now knows how to do it without even breaking the law. All it needs is a few chaps planted at the four corners of the Underground system, puffing on electronic cigarettes at an agreed moment. If any of them is shot through the head by an armed response unit, the irony that a device designed to remove the health risk from inhaling nicotine would have proved more lethal than 30 years of Marlboro reds might be lost in all the excitement, but nothing’s perfect.

With the confluence of Diamond’s disgrace and the opening of the Shard as a monument to City avarice, and with Osborne vs Balls reducing parliamentary debate to the status of a pro wrestling grudge match between Mick McManus and Giant Haystacks, what a blue riband week it has been for those addicted to wondering how this country has become such a madhouse. But nothing has crystallised the lunacy like the Wisp of Smoke Siege on the M6. In fact, noting that a passenger quoted saying “I felt scared, my legs were like jelly” is named as Vermilion Von Kangur, I suspect it must be a feverish dream after all, and that this is what comes of not finishing a course of antibiotics.